Dendrimer compound and organic luminescent device employing the same

ABSTRACT

A dendrimer compound characterized by comprising a core represented by the following formula (1-1), (1-2), (1-3), or (1-4) and at least one kind of dendritic structure selected among dendritic structures represented by the following formulae (3) and (4).

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.10/571,568, filed Aug. 15, 2006, now allowed, which is a National PhaseApplication of PCT/JP04/13585, filed Sep. 10, 2004, and claims benefitto Japanese Patent Application No. 2003-321522, filed Sep. 12, 2003, thecontents of each of which are incorporated herein by reference in theirentirety.

TECHNICAL FIELD

The present invention relates to a dendrimer compound, a raw materialcompound thereof and an organic luminescent device (hereinaftersometimes referred to as an organic LED) in which the dendrimer compoundis used.

BACKGROUND ART

High molecular weight luminescent materials and high molecular weightcharge transport materials have been variously studied since they aresoluble in solvents unlike low molecular weight materials and thus canbe formed into a luminescent layer or a charge transport layer of aluminescent device by coating.

Linear polymers are generally known as such high molecular weightmaterials.

On the other hand, applications of dendrimer compounds having a specificpolymer structure to luminescent materials and charge transportmaterials have been recently reported (Patent Documents 1, 2, 3).

-   Patent Document 1 JP-A-11-40871-   Patent Document 2 JP-A-11-171812-   Patent Document 3 WO02/067343

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention

An object of the present invention is to provide a novel dendrimercompound useful as a luminescent material or a charge transportmaterial, a raw material compound thereof and an organic luminescentdevice in which the dendrimer compound is used.

Means for Solving the Problems

The present inventors have conducted intensive studies to solve theabove-described problem and as a result, have found that a dendrimercompound having a structure represented by the following formula (5) isuseful as a luminescent material and a charge transport material, andthe present invention has been completed.

Accordingly, the present invention is as follows.

(i) The present invention relates to a dendrimer compound characterizedby comprising a core represented by the following formula (1-1), (1-2),(1-3) or (1-4) and at least one dendritic structure selected fromdendritic structures represented by the following formula (3) or (4).The present invention also relates to a polymer compound characterizedby comprising the dendrimer bonded to an atom constituting the mainchain structure or a side chain of the polymer compound.

The dendrimer compound is characterized by comprising a core representedby the following formula (1-1), (1-2), (1-3) or (1-4) and at least onedendritic structure selected from dendritic structures represented bythe following formula (3) or (4):

wherein a unit CA, a unit CB, a unit CC and a unit CD each independentlyrepresent an aromatic ring, a metal complex structure, a structurerepresented by the following formula (5):

wherein a ring A and a ring B each independently represent an aromaticring, X represents —O—, —S—, —S(═O)—, —SO₂—, —B(R₄)—, —Si(R₂)(R₃)—,—P(R₄)— or —PR₅(═O)—, and R₁, R₂, R₃, R₄ and R₅ each independentlyrepresent a substituent selected from an alkyl group, an alkoxy group,an alkylthio group, an aryl group, an aryloxy group, an arylthio group,an arylalkyl group, an arylalkoxy group, an arylalkylthio group, anarylalkenyl group, arylalkynyl group, an amino group, a substitutedamino group and a monovalent heterocyclic group,or a structure in which two or more structures selected from an aromaticring, a metal complex structure and a structure represented by thefollowing formula (5), which may be the same or different, are bondeddirectly or via a divalent group shown in the following (L-1):

wherein R′ represents a group selected from a hydrogen atom, an alkylgroup, an alkoxy group, an aryl group and an aryloxy group, and when aplurality of R's are present, R's may be the same or different; a, b andc each independently represent an integer of 1 to 12; and d representsan integer of 1 to 11;a unit DA and a unit DB each independently represent an aromatic ring, ametal complex structure, a structure represented by the followingformula (5), or a structure in which two or more structures selectedfrom an aromatic ring, a metal complex structure and a structurerepresented by the following formula (5), which may be the same ordifferent, are bonded; at least one of the core and the dendriticstructure contains a structure represented by the formula (5), and L isa direct bond or a linking group selected from the following (L-2):

wherein R₁′ represents a hydrogen atom, an alkyl group, an alkoxy group,an aryl group or an aryloxy group, and when a plurality of R₁'s arepresent, R₁'s may be the same or different.(ii) The dendrimer compound according to the above (i), wherein the unitCC contains a metal complex structure.(iii) The dendrimer compound according to the above (i), wherein theunit CD contains a metal complex structure.(iv) The dendrimer compound according to the above (i), wherein the unitCA or the unit CB contains a metal complex structure.(v) The dendrimer compound according to any one of the above (i) to(iv), whose number of generations is 1 to 5.(vi) The dendrimer compound according to any one of the above (i) to(v), comprising a chemical structure in which at least one dendriticstructure selected from dendritic structures represented by the formula(3) and the formula (4) is regularly repeated.(vii) The dendrimer compound according to any one of the above (i) to(vi), wherein the core represented by the formula (1-2) is representedby the following formula (6-1), (6-2) or (6-3):

wherein the ring A, the ring B and X are as defined above; Ar₁represents a divalent aromatic ring or a divalent metal complexstructure; Ar₂ represents a trivalent aromatic ring or a trivalent metalcomplex structure; and aa and bb each independently represent 0 or 1.(viii) The dendrimer compound according to any one of the above (i) to(vi), wherein the core represented by the formula (1-3) is representedby the following formula (7-1), (7-2) or (7-3):

wherein the ring A, the ring B and X are as defined above; Ar₁represents a divalent aromatic ring or a divalent metal complexstructure; Ar₂ represents a trivalent aromatic ring or a trivalent metalcomplex structure; and aa and bb each independently represent 0 or 1.(ix) The dendrimer compound according to any one of the above (i) to(vi), wherein the core represented by the formula (1-4) is representedby the following formula (8-1), (8-2), (8-3) or (8-4):

wherein the ring A, the ring B and X are as defined above; Ar₃, Ar₄, Ar₅and Ar₆ each independently represent a trivalent aromatic ring or atrivalent metal complex structure; and Ar₇ represents a tetravalentaromatic ring or a tetravalent metal complex structure.(x) The dendrimer compound according to any one of the above (i) to(ix), wherein the dendritic structure represented by the formula (3) isrepresented by the formula (7-1), (7-2) or (7-3).(xi) The dendrimer compound according to any one of the above (i) to(ix), wherein the dendritic structure represented by the formula (4) isrepresented by the formula (7-1), (7-2), (7-3) or (7-4).(xii) The dendrimer compound according to any one of the above (i) to(xi), wherein the ring A and the ring B are an aromatic hydrocarbonring.(xiii) The dendrimer compound according to any one of the above (i) to(xii), wherein at least one of the core and the dendritic structurecontains a metal complex structure.(xiv) The dendrimer compound according to any one of the above (i) to(xiii), further comprising a surface group in addition to the core andthe dendritic structure.(xv) A composition comprising at least one material selected from a holetransport material, an electron transport material and a luminescentmaterial, and the dendrimer compound according to any one of the above(i) to (xiv).(xvi) A composition characterized by comprising the dendrimer compoundaccording to any one of the above (i) to (xiv) and a conjugated polymercompound containing an aromatic ring in the main chain.(xvii) The composition according to the above (xvi), further comprisingat least one material selected from a hole transport material, anelectron transport material and a luminescent material.(xviii) An ink composition characterized by comprising the dendrimercompound or the composition according to any one of the above (i) to(xvii).(xix) The ink composition according to the above (xviii), having aviscosity of 1 to 100 mPa·s at 25° C.(xx) A luminescent thin film characterized by comprising the dendrimercompound or the composition according to any one of the above (i) to(xvii).(xxi) A conductive thin film characterized by comprising the dendrimercompound or the composition according to any one of the above (i) to(xvii).(xxii) An organic semiconductor thin film characterized by comprisingthe dendrimer compound or the composition according to any one of theabove (i) to (xvii).(xxiii) An organic luminescent device characterized by comprising alayer containing the dendrimer compound or the composition according toany one of the above (i) to (xvii) between electrodes of an anode and acathode.(xxiv) The organic luminescent device according to the above (xxiii),wherein the layer containing the dendrimer compound or the compositionaccording to any one of the above (i) to (xvii) is a luminescent layer.(xxv) A planar light source characterized by comprising the organicluminescent device according to the above (xxiii) or (xxiv).(xxvi) A segment display device characterized by comprising the organicluminescent device according to the above (xxiii) or (xxiv).(xxiii) A dot matrix display device characterized by comprising theorganic luminescent device according to the above (xxiii) or (xxiv).(xxviii) A liquid crystal display device characterized by comprising theorganic luminescent device according to the above (xxiii) or (xxiv) as abacklight.(xxix) An illumination characterized by comprising the organicluminescent device according to the above (xxiii) or (xxiv).

Advantages of the Invention

The dendrimer compound of the present invention is a novel dendrimercompound useful as a luminescent material or a charge transportmaterial.

BEST MODE FOR CARRYING OUT THE INVENTION

The dendrimer compound of the present invention comprises a corerepresented by the above formula (1-1), (1-2), (1-3) or (1-4) and atleast one dendritic structure selected from dendritic structuresrepresented by the above formula (3) or (4).

Dendrimer compounds are described in, for example, JP-A-11-140180,JP-A-2002-220468, “Dendritic Molecules” published by VCH Publishers,1996, “Dendorima no Bunshisekkei (Molecular Design of Dendrimers)” and“Dendorima no Tasaina Kino (Dendrimers and Their Various Functions)”,pp. 20-40, Chemistry today, June 1998, and “Dendrima noHisenkeikogakuzairyo heno Oyo (Dendrimers, Application to NonlinearOptical Materials)” in Kobunshi Vol. 47, November (1998). In the presentinvention, the dendrimer compound refers to a dendritic compound havinga chemical structure composed of a core (nucleus) and a dendriticstructure containing a branched unit. The dendritic structure as usedherein refers to a branched unit of DA or DB and three or four branchedportions containing a linking group. The dendritic structure andrepeated part thereof are called dendron.

To describe the size of dendrimers, a notion of generation is used. Inthe present invention, the core, which is the most central part, refersto the central structure including 1, 2, 3 or 4 branched portionscontaining a linking group. The first dendritic structure or branchedunit next to the core including its terminal is defined as the firstgeneration. When there is another dendritic structure outside thedendritic structure of the first generation, the succeeding dendriticstructure or branched unit including its terminal is defined as thesecond generation. Likewise, for the third and the followinggenerations, a subsequent dendritic structure or branched unit includingits terminal is defined as the next generation.

In the dendrimer of the present invention, a preferred number ofgenerations is in the range of 1 to 5, more preferably 1 to 3.

Examples of structures of dendrimer compounds include structurescontaining a dendron in which one kind of dendritic structure isregularly repeated, which are represented by the following formula(18-1), (18-2), (18-3) or (18-4).

Examples of structures of the dendrimer compounds of the presentinvention also include structures which contain an identical dendriticstructure within one dendron but contain two types of dendrons having adifferent number of branches in one generation represented by thefollowing formula (18-5); structures which contain an identicaldendritic structure within one dendron and contain two or more kinds ofdendrons having the same number of branches but a different kind ofbranched unit in one generation represented by the following formula(18-6); structures which contain one kind of dendron whose dendriticstructure is different in each generation represented by the followingformula (18-7); and structures represented by the formula (18-8) inwhich the above are combined.

Examples of structures of dendrimer compounds also include structuresrepresented by the following formula (18-9), (18-9-1), (18-9-2),(18-9-3) or (18-9-4) in which part of the dendrons has a regular repeatstructure.

Examples of structures of dendrimer compounds also include those inwhich L in the formulas (18-1) to (18-9), (18-9-1), (18-9-2), (18-9-3)and (18-9-4) is different in each generation or dendron.

In view of ease in synthesis while it depends on the synthesis method,preferred structures of dendrimer compounds are structures containing adendron in which one kind of dendritic structure is regularly repeatedrepresented by the above formula (18-1), (18-2), (18-3) or (18-4);structures which contain an identical dendritic structure within onedendron but contain two types of dendrons having a different number ofbranches in one generation represented by the above formula (18-5); andstructures which contain an identical dendritic structure within onedendron and contain two or more kinds of dendrons having the same numberof branches but a different kind of branched unit in one generationrepresented by the above formula (18-6). Particularly preferred arestructures containing a dendron in which one kind of dendritic structureis regularly repeated represented by the above formula (18-1), (18-2),(18-3) or (18-4).

Herein, the unit CA, the unit CB, the unit CC and the unit CD eachindependently represent an aromatic ring, a metal complex structure, astructure represented by the following formula (5), or a structure inwhich two or more structures selected from an aromatic ring, a metalcomplex structure and a structure represented by the following formula(5), which may be the same or different, are bonded directly or via adivalent group shown in the following (L-1). The following group in theformula (1-1):

is a monovalent group. The following group in the formula (1-2):

is a divalent group. The following group in the formula (1-3):

is a trivalent group. And the following group in the formula (1-4):

is a tetravalent group.

The unit DA and the unit DB each independently represent an aromaticring, a metal complex structure, a structure represented by thefollowing formula (5), or a structure in which two or more structuresselected from an aromatic ring, a metal complex structure and astructure represented by the following formula (5), which may be thesame or different, are bonded.

The following group in the formula (3):

is a trivalent group, and the following group in the formula (4):

is a tetravalent group.

In the above formulas (18-6), (18-7) and (18-8), the unit DA′ and theunit DA″ have the same definition as the unit DA. The unit DA′, the unitDA″ and the unit DA represent a unit different from each other. The unitDB′ has the same definition as the unit DB, and the unit DB′ and theunit DB represent a ring different from each other.

Examples of aromatic rings include aromatic hydrocarbon rings such as abenzene ring, a naphthalene ring, an anthracene ring, a tetracene ring,a pentacene ring, a pyrene ring and a phenanthrene ring; andheteroaromatic rings such as a pyridine ring, a phenanthroline ring, aquinoline ring, an isoquinoline ring, a thiophene ring, a furan ring anda pyrrole ring.

The metal complex structure is a metal complex containing an organicligand. Examples of organic ligands include 8-quinolinol and derivativesthereof, benzoquinolinol and derivatives thereof, 2-phenylpyridine andderivatives thereof, 2-phenylbenzothiazole and derivatives thereof,2-phenylbenzoxazole and derivatives thereof, porphyrin and derivativesthereof, acetylacetone and derivatives thereof, phthalocyanine andderivatives thereof, salen and derivatives thereof, 1,10-phenanthrolineand derivatives thereof and 2,6-di(2-pyridyl)-pyridine and derivativesthereof. Examples of central metal of the complex include aluminum,zinc, beryllium, ruthenium, rhodium, rhenium, iridium, platinum, gold,europium and terbium.

Examples of metal complexes include tris(8-quinolinol) aluminum andtriplet luminescence complexes such as Ir(ppy)₃ and Btp₂Ir(acac) inwhich the central metal is iridium, PtOEP in which the central metal isplatinum and Eu(TTA)₃phen in which the central metal is europium.

In the aforementioned formula (5), the ring A and the ring B eachindependently represent an aromatic ring. The aromatic ring is asdefined above. The aromatic rings of the ring A and the ring B may bethe same or different.

Specific examples of unsubstituted structures of the formula (5) are asfollows.

X represents —O—, —S—, —S(═O)—, —SO₂—, —B(R₂)—, —Si(R₂)(R₃)—, —P(R₄)— or—PR₅(═O)—, and R₁, R₂, R₃, R₄ and R₅ each independently represent asubstituent selected from an alkyl group, an alkoxy group, an alkylthiogroup, an aryl group, an aryloxy group, an arylthio group, an arylalkylgroup, an arylalkoxy group, an arylalkylthio group, an arylalkenylgroup, an arylalkynyl group, an amino group, a substituted amino groupand a monovalent heterocyclic group.

The aromatic ring, the metal complex structure and the structurerepresented by the formula (5) described above may have a substituent Q.Examples of substituents Q include an alkyl group, an alkoxy group, analkylthio group, an aryl group, an aryloxy group, an arylthio group, anarylalkyl group, an arylalkoxy group, an arylalkylthio group, anarylalkenyl group, an arylalkynyl group, an amino group, a substitutedamino group, a silyl group, a substituted silyl group, a silyloxy group,a substituted silyloxy group, a halogen atom, an acyl group, an acyloxygroup, imine residue, an amide group, an acid imide group, a monovalentheterocyclic group, a carboxyl group, a substituted carboxyl group and acyano group. Preferred are an alkyl group, an alkoxy group, an alkylthiogroup, an aryl group, an aryloxy group, an arylthio group, a substitutedamino group, a substituted silyl group, a substituted silyloxy group anda monovalent heterocyclic group. An unsubstituted aromatic ringgenerally has 6 to 60 carbon atoms, preferably 6 to 20 carbon atoms.

Herein, the alkyl group may be linear, branched or cyclic. An alkylgroup generally has 1 to 20 carbon atoms. Specific examples thereofinclude a methyl group, an ethyl group, a propyl group, an i-propylgroup, a butyl group, an i-butyl group, a t-butyl group, a pentyl group,a hexyl group, a cyclohexyl group, a heptyl group, an octyl group, a2-ethylhexyl group, a nonyl group, a decyl group, a 3,7-dimethyloctylgroup, a lauryl group, a trifluoromethyl group, a pentafluoroethylgroup, a perfluorobutyl group, a perfluorohexyl group and aperfluorooctyl group. Preferred are a pentyl group, a hexyl group, anoctyl group, 2-ethyl hexyl group, a decyl group and a 3,7-dimethyloctylgroup.

The alkoxy group may be linear, branched or cyclic. An alkoxy groupgenerally has 1 to 20 carbon atoms. Specific examples thereof include amethoxy group, an ethoxy group, a propyloxy group, an i-propyloxy group,a butoxy group, an i-butoxy group, a t-butoxy group, a pentyloxy group,a hexyloxy group, a cyclohexyloxy group, a heptyloxy group, an octyloxygroup, a 2-ethylhexyloxy group, a nonyloxy group, a decyloxy group, a3,7-dimethyloctyloxy group, a lauryloxy group, a trifluoromethoxy group,a pentafluoroethoxy group, a perfluorobutoxy group, a perfluorohexylgroup, a perfluorooctyl group, a methoxymethyloxy group, a2-methoxyethyloxy group. Preferred are a pentyloxy group, a hexyloxygroup, an octyloxy group, a 2-ethylhexyloxy group, a decyloxy group anda 3,7-dimethyloctyloxy group.

The alkylthio group may be linear, branched or cyclic. An alkylthiogroup generally has 1 to 20 carbon atoms. Specific examples thereofinclude a methylthio group, an ethylthio group, a propylthio group, ani-propylthio group, a butylthio group, an i-butylthio group, at-butylthio group, a pentylthio group, a hexylthio group, acyclohexylthio group, a heptylthio group, an octylthio group, a2-ethylhexylthio group, a nonylthio group, a decylthio group, a3,7-dimethyloctylthio group, a laurylthio group and atrifluoromethylthio group. Preferred are a pentylthio group, a hexylthiogroup, an octylthio group, a 2-ethylhexylthio group, a decylthio groupand a 3,7-dimethyloctylthio group.

An aryl group generally has 6 to 60 carbon atoms. Specific examplesthereof include a phenyl group, a C₁-C₁₂ alkoxyphenyl group (C₁-C₁₂means having 1 to 12 carbon atoms; the same applies below), a C₁-C₁₂alkylphenyl group, a 1-naphthyl group, a 2-naphthyl group, a1-anthracenyl group, a 2-anthracenyl group, a 9-anthracenyl group and apentafluorophenyl group. Preferred are a C₁-C₁₂ alkoxyphenyl group and aC₁-C₁₂ alkylphenyl group. Herein, the aryl group refers to an atomicgroup in which a hydrogen atom is missing from aromatic hydrocarbon.Aromatic hydrocarbons include those containing a benzene ring or a fusedring and those in which two or more independent benzene rings or fusedrings are bonded directly or via a group such as vinylene.

Specific examples of C₁-C₁₂ alkoxy include methoxy, ethoxy, propyloxy,i-propyloxy, butoxy, i-butoxy, t-butoxy, pentyloxy, hexyloxy,cyclohexyloxy, heptyloxy, octyloxy, 2-ethylhexyloxy, nonyloxy, decyloxy,3,7-dimethyloctyloxy and lauryloxy.

Specific examples of C₁-C₁₂ alkyl include methyl, ethyl, propyl,i-propyl, butyl, i-butyl, t-butyl, pentyl, hexyl, cyclohexyl, heptyl,octyl, 2-ethylhexyl, nonyl, decyl, 3,7-dimethyloctyl and lauryl.

An aryloxy group generally has 6 to 60 carbon atoms. Specific examplesthereof include a phenoxy group, a C₁-C₁₂ alkoxyphenoxy group, a C₁-C₁₂alkylphenoxy group, a 1-naphthyloxy group, a 2-naphthyloxy group and apentafluorophenyloxy group. Preferred are a C₁-C₁₂ alkoxyphenoxy groupand a C₁-C₁₂ alkylphenoxy group.

The arylthio group usually has about 6 to 60 carbon atoms. Specificexamples include a phenylthio group, C₁-C₁₂ alkoxyphenylthio group,C₁-C₁₂ alkylphenylthio group, 1-naphthylthio group, 2-naphthylthiogroup, pentafluorophenylthio group and the like, wherein the C₁-C₁₂alkoxyphenylthio group and C₁-C₁₂ alkylphenylthio group are preferable.

The arylalkyl group usually has about 7 to 60 carbon atoms. Specificexamples include phenyl-C₁-C₁₂ alkyl groups, such as a phenylmethylgroup, phenylethyl group, phenylbutyl group, phenylpentyl group,phenylhexyl group, phenylheptyl group, and phenyloctyl group; C₁-C₁₂alkoxyphenyl-C₁-C₁₂ alkyl group, C₁-C₁₂ alkylphenyl-C₁-C₁₂ alkyl group,1-naphthyl-C₁-C₁₂ alkyl group, 2-naphthyl-C₁-C₁₂ alkyl group and thelike, wherein the C₁-C₁₂ alkoxyphenyl-C₁-C₁₂ alkyl group, and C₁-C₁₂alkylphenyl-C₁-C₁₂ alkyl group are preferable.

The arylalkoxy group usually has about 7 to 60 carbon atoms. Specificexamples include phenyl-C₁-C₁₂ alkoxy groups, such as a phenylmethoxygroup, phenylethoxy group, phenylbutoxy group, phenylpentyloxy group,phenylhexyloxy group, phenylheptyloxy group, and phenyloctyloxy group;C₁-C₁₂ alkoxyphenyl-C₁-C₁₂ alkoxy group, C₁-C₁₂ alkylphenyl-C₁-C₁₂alkoxy group, 1-naphthyl-C₁-C₁₂ alkoxy group, 2-naphthyl-C₁-C₁₂ alkoxygroup and the like, wherein the C₁-C₁₂ alkoxyphenyl-C₁-C₁₂ alkoxy groupand C₁-C₁₂ alkylphenyl-C₁-C₁₂ alkoxy group are preferable.

The arylalkylthio group usually has about 7 to 60 carbon atoms. Specificexamples include a phenyl-C₁-C₁₂ alkylthio group, C₁-C₁₂alkoxyphenyl-C₁-C₁₂ alkylthio group, C₁-C₁₂ alkylphenyl-C₁-C₁₂ alkylthiogroup, 1-naphthyl-C₁-C₁₂ alkylthio group, 2-naphthyl-C₁-C₁₂ alkylthiogroup and the like, wherein the C₁-C₁₂ alkoxyphenyl-C₁-C₁₂ alkylthiogroup and C₁-C₁₂ alkylphenyl-C₁-C₁₂ alkylthio group are preferable.

The arylalkenyl group usually has about 8 to 60 carbon atoms. Specificexamples include a phenyl-C₂-C₁₂ alkenyl group, C₁-C₁₂alkoxyphenyl-C₂-C₁₂ alkenyl group, C₁-C₁₂ alkylphenyl-C₂-C₁₂ alkenylgroup, 1-naphthyl-C₂-C₁₂ alkenyl group, 2-naphthyl-C₂-C₁₂ alkenyl groupand the like, wherein the C₁-C₁₂ alkoxyphenyl-C₂-C₁₂ alkenyl group andC₁-C₁₂ alkylphenyl-C₂-C₁₂ alkenyl group are preferable.

The arylalkynyl group usually has about 8 to 60 carbon atoms. Specificexamples include a phenyl-C₂-C₁₂ alkynyl group, C₁-C₁₂alkoxyphenyl-C₂-C₁₂ alkynyl group, C₁-C₁₂ alkylphenyl-C₂-C₁₂ alkynylgroup, 1-naphthyl-C₂-C₁₂ alkynyl group, 2-naphthyl-C₂-C₁₂ alkynyl groupand the like, wherein the C₁-C₁₂ alkoxyphenyl-C₂-C₁₂ alkynyl group andC₁-C₁₂ alkylphenyl-C₂-C₁₂ alkynyl group are preferable.

Examples of the substituted amino group include amino groups having oneor two substituents selected from an alkyl group, aryl group, arylalkylgroup, or a monovalent heterocyclic group. The substituted amino groupusually has about 1 to 60 carbon atoms. Specific examples include amethylamino group, dimethylamino group, ethylamino group, diethylaminogroup, propylamino group, dipropylamino group, i-propylamino group,diisopropylamino group, butylamino group, i-butylamino group,t-butylamino group, pentylamino group, hexylamino group, cyclohexylaminogroup, heptylamino group, octylamino group, 2-ethylhexylamino group,nonylamino group, decylamino group, 3,7-dimethyloctylamino group,laurylamino group, cyclopentylamino group, dicyclopentylamino group,cyclohexylamino group, dicyclohexylamino group, pyrrolidyl group,piperidyl group, ditrifluoromethylamino group, phenyl amino group,diphenylamino group, C₁-C₁₂ alkoxyphenylamino group, di(C₁-C₁₂alkoxyphenyl)amino group, di(C₁-C₁₂ alkylphenyl)amino group,1-naphthylamino group, 2-naphthylamino group, pentafluorophenylaminogroup, pyridylamino group, pyridazinylamino group, pyrimidylamino group,pyrazylamino group, triazylamino group phenyl-C₁-C₁₂ alkylamino group,C₁-C₁₂ alkoxyphenyl-C₁-C₁₂ alkylamino group, C₁-C₁₂ alkyl phenyl-C₁-C₁₂alkylamino group, di(C₁-C₁₂ alkoxyphenyl-C₁-C₁₂ alkyl)amino group,di(C₁-C₁₂ alkylphenyl-C₁-C₁₂ alkyl)amino group, 1-naphthyl-C₁-C₁₂alkylamino group, 2-naphthyl-C₁-C₁₂ alkylamino group, carbazolyl group,and the like.

Examples of the substituted silyl group include silyl groups having 1, 2or 3 substituents selected from an alkyl group, aryl group, arylalkylgroup, and monovalent heterocyclic group. The substituted silyl groupusually has about 1 to 60 carbon atoms.

Specific examples include a trimethylsilyl group, triethylsilyl group,tripropylsilyl group, tri-1-propylsilyl group, dimethyl-1-propylsilylgroup, diethyl-1-propylsilyl group, t-butyldimethylsilyl group,pentyldimethylsilyl group, hexyldimethylsilyl group, heptyldimethylsilylgroup, octyldimethylsilyl group, 2-ethylhexyl-dimethylsilyl group,nonyldimethylsilyl group, decyldimethylsilyl group,3,7-dimethyloctyl-dimethylsilyl group, lauryldimethylsilyl group,phenyl-C₁-C₁₂ alkylsilyl group, C₁-C₁₂ alkoxyphenyl-C₁-C₁₂ alkylsilylgroup, C₁-C₁₂ alkylphenyl-C₁-C₁₂ alkylsilyl group, 1-naphthyl-C₁-C₁₂alkylsilyl group, 2-naphthyl-C₁-C₁₂ alkylsilyl group, phenyl-C₁-C₁₂alkyldimethylsilyl group, triphenylsilyl group, tri-p-xylylsilyl group,tribenzylsilyl group, diphenylmethylsilyl group, t-butyldiphenylsilylgroup, dimethylphenylsilyl group, trimethoxysilyl group, triethoxysilylgroup, tripropyloxysilyl group, tri-1-propylsilyl group,dimethyl-1-propylsilyl group, methyldimethoxysilyl group,ethyldimethoxysilyl group and the like.

Examples of the substituted silyloxy group include silyloxy groupshaving 1, 2 or 3 substituents selected from an alkyl group, aryl group,arylalkyl group, and monovalent heterocyclic group. The substitutedsilyloxy group usually has about 1 to 60 carbon atoms.

Specific examples include a trimethylsilyloxy group, triethylsilyloxygroup, tripropylsilyloxy group, tri-1-propylsilyloxy group,dimethyl-1-propylsilyloxy group, diethyl-1-propylsilyloxy group,t-butyldimethylsilyloxy group, pentyldimethylsilyloxy group,hexyldimethylsilyloxy group, heptyldimethylsilyloxy group,octyldimethylsilyloxy group, 2-ethylhexyl-dimethylsilyloxy group,nonyldimethylsilyloxy group, decyldimethylsilyloxy group,3,7-dimethyloctyl-dimethylsilyloxy group, lauryldimethylsilyloxy group,phenyl-C₁-C₁₂ alkylsilyloxy group, C₁-C₁₂alkoxyphenyl-C₁-C₁₂alkylsilyloxy group, C₁-C₁₂ alkylphenyl-C₁-C₁₂alkylsilyloxy group, 1-naphthyl-C₁-C₁₂ alkylsilyloxy group,2-naphthyl-C₁-C₁₂ alkylsilyloxy group, phenyl-C₁-C₁₂ alkyldimethylsilyloxy group, triphenylsilyloxy group, tri-p-xylylsilyloxygroup, tribenzylsilyloxy group, diphenylmethylsilyloxy group,t-butyldiphenylsilyloxy group, dimethylphenylsilyloxy group,trimethoxysilyloxy group, triethoxysilyloxy group, tripropyloxysilyloxygroup, tri-1-propylsilyloxy group, dimethyl-1-propylsilyloxy group,methyldimethoxysilyloxy group, ethyldimethoxysilyloxy group, and thelike.

Examples of the halogen atom include a fluorine atom, chlorine atom,bromine atom and iodine atom.

The acyl group usually has about 2 to 20 carbon atoms. Specific examplesinclude an acetyl group, propionyl group, butyryl group, isobutyrylgroup, pivaloyl group, benzoyl group, trifluoroacetyl group,pentafluorobenzoyl group and the like.

The acyloxy group usually has about 2 to 20 carbon atoms Specificexamples include an acetoxy group, propionyloxy group, butyryloxy group,isobutyryloxy group, pivaloyloxy group, benzoyloxy group, trifluoroacetyloxy group, pentafluorobenzoyloxy group and the like.

Examples of the imine residue include residues in which one hydrogenatom is removed from an imine compound (referring to an organic compoundhaving —N═C— in the molecule; examples include aldimine, ketamine andcompounds thereof whose hydrogen atom on the nitrogen is substitutedwith an alkyl group or the like). The imine reside group has about 2 to20 carbon atoms. Specific examples include the following groups.

The amide group usually has about 1 to 20 carbon atoms. Specificexamples include a formamide group, acetamide group, propioamide group,butyroamide group, benzamide group, trifluoroacetamide group,pentafluorobenzamide group, diformamide group, diacetamide group,dipropioamide group, dibutyroamide group, dibenzamide group, ditrifluoroacetamide group, dipentafluorobenzamide group and the like.

The acid imide group can be a residue obtained by removing a hydrogenatom bound to the nitrogen atom of the acid imide, and have about 4 to20 carbon atoms. Specific examples include the following groups.

In the above examples, Me represents a methyl group.

The monovalent heterocyclic group is an atomic group in which a hydrogenatom is removed from a heterocyclic compound, which may have asubstituent.

An unsubstituted monovalent heterocyclic group usually has about 4 to 60carbon atoms, and preferably 4 to 20.

Examples of the monovalent heterocyclic group include a thienyl group,C₁-C₁₂ alkylthienyl group, pyroryl group, furyl group, pyridyl group,C₁-C₁₂ alkylpyridyl group and the like, wherein the thienyl group,C₁-C₁₂ alkylthienyl group, pyridyl group, and C₁-C₁₂ alkylpyridyl groupare preferable.

The substituted carboxyl group usually has about 2 to 60 carbon atoms,and refers to a carboxyl group substituted with an alkyl group, arylgroup, arylalkyl group, or monovalent heterocyclic group. Examplesthereof include a methoxycarbonyl group, ethoxycarbonyl group,propoxycarbonyl group, i-propoxycarbonyl group, butoxycarbonyl group,i-butoxycarbonyl group, t-butoxycarbonyl group, pentyloxycarbonyl group,hexyloxycarbonyl group, cyclohexyloxycarbonyl group, heptyloxycarbonylgroup, octyloxycarbonyl group, 2-ethylhexyloxycarbonyl group,nonyloxycarbonyl group, decyloxycarbonyl group,3,7-dimethyloctyloxycarbonyl group, dodecyloxycarbonyl group,trifluoromethoxycarbonyl group, pentafluoroethoxycarbonyl group,perfluorobutoxycarbonyl group, perfluorohexyloxycarbonyl group,perfluorooctyloxycarbonyl group, phenoxycarbonyl group,naphthoxycarbonyl group, pyridyloxycarbonyl group and the like.

While the below example possesses a plurality of Rs contained in the onestructural formula, these Rs may be the same or different. Here R is ahydrogen atom, or, as mentioned above, is defined in the same manner asthe substituent Q which can have an aromatic ring, a metal complexstructure, and the structure represented by the above formula (5). Toimprove solubility into a solvent, it is preferable that at least one ofthe Rs in one structural formula is other than a hydrogen atom. In thepresent invention, Rs other than a hydrogen atom are referred to as a“surface group”. In addition, it is preferable that the form of therepeating unit including the substituent has little symmetry. Moreover,it is preferable that at least one of the Rs in one structural formulacontains a cyclic or branched alkyl group. A plurality of Rs may beconnected to form a ring.

In the above formula, when R is a substituent containing an alkyl group,the alkyl group may be linear, branched or cyclic, or may be acombination thereof. Examples of non-linear alkyl chains include anisoamyl group, 2-ethylhexyl group, 3,7-dimethyloctyl group, cyclohexylgroup, 4-C₁-C₁₂ alkylcyclohexyl group and the like.

Furthermore, the alkyl group methyl group or methylene group of thealkyl-group-containing-group may be replaced by a group containing ahetero atom, or a methyl or methylene group which is substituted withone or more fluorine atoms. Examples of the hetero atom include anoxygen atom, sulfur atom, nitrogen atom and the like.

For the of the following group in formula (1-1),

specific examples include the below monovalent aromatic hydrocarboncyclic groups.

For the following group in formula (1-2),

specific examples include the below divalent aromatic hydrocarbon cyclicgroups.

For the following group in formula (1-3),

and the following group in formula (3),

specific examples include the below trivalent aromatic hydrocarboncyclic groups.

Further examples include the below trivalent heteroaromatic cyclicgroups.

Further examples include the following groups having a trivalent metalcomplex structure.

Further examples include the below trivalent groups having a structurerepresented by the above-described formula (5).

For the following group in formula (1-3),

and the following group in formula (3),

examples include the below trivalent groups in which 2 or more of thesame or different structures selected from an aromatic ring, metalcomplex structure or the structures represented by above formula (5) areconnected together.

For the following group in formula (1-3),

examples include the below trivalent groups in which 2 or more of thesame or different structures selected from an aromatic ring, metalcomplex structure, structures represented by above formula (5) and thelike are connected together by a divalent group represented by the above(L-1).

R in the examples represented by the above formulas A1 to A116 isdefined in the same manner as above. X is also defined in the samemanner as that in the above formula (5).

For the following group in formula (1-4),

and the following group in formula (4),

specific examples include the below tetravalent aromatic hydrocarboncyclic groups.

Further examples include the below tetravalent heteroaromatic cyclicgroups.

Further examples include the following groups having a tetravalent metalcomplex structure.

Further examples include the below tetravalent groups consisting of astructure represented by the above formula (5).

For the following group in formula (1-4),

and the following group in formula (4),

examples include the below quartervalent groups in which 2 or more ofthe same or different structures selected from an aromatic ring, metalcomplex structure and the structures represented by above formula (5)are connected together.

For the following group in formula (1-4),

examples include the below quartervalent groups in which 2 or more ofthe same or different structures selected from an aromatic ring, metalcomplex structure and the structures represented by above formula (5)are connected together by a divalent group represented by the above(L-1).

R in the examples represented by the above formulas B1 to B89 is definedin the same manner as above. X is also defined in the same manner asthat in the above formula (5).

If unit CA, unit CB unit CC or unit CD, unit DA, or unit DB have anaromatic ring, a benzene ring, naphthalene ring, anthracene ring,pyridine ring, triazine ring, quinoline ring, and isoquinoline ring arepreferred as the aromatic ring. Such an aromatic ring preferably has oneor more substituent groups. The number of aromatic rings is preferablybetween 1 and 10 for each unit.

If unit CA, unit CB unit CC or unit CD, unit DA or unit DB have a metalcomplex structure, the number of metal complex structures is preferablybetween 1 and 6 for each unit, and more preferably between 1 and 4.

Having the structure represented by the above formula (5) is anessential component of the dendrimer compound of the present invention.That is, at least one of the core units (unit CA, and unit CB unit CC orunit CD) and the unit in the dendritic structure (unit DA and/or unitDB) has a structure represented by the above formula (5).

If the following group in formula (1-3),

and the following group in formula (3),

have a structure represented by the above formula (5), trivalent groupssuch as those represented below are preferable.

If the following group in formula (2),

and the following group in formula (4),

have a structure represented by the above formula (5), tetravalentgroups such as those represented below are preferable.

The ring A, ring B and X in the above formulas are as defined above. Ar₄represents a divalent group having a divalent aromatic ring or metalcomplex. Ar₂, Ar₃, Ar₄, Ar₅, and Ar₆ represent a trivalent group eachindependently having a trivalent aromatic ring or metal complex. Ar₇represents a tetravalent group having a tetravalent aromatic ring ormetal complex. “aa” and “bb” each independently represent 0 or 1.

The term “divalent aromatic ring” refers to arylene groups and divalentheterocyclic groups.

Here, an arylene group is an atomic group in which two hydrogen atomsare removed from an aromatic hydrocarbon. The arylene group can alsoinclude structures having a benzene ring or a condensed ring, and thoseincluding two or more independent benzene rings or condensed ringsbonded directly or through a group such as a vinylene group or the like.A “divalent heterocyclic group” is an atomic group in which two hydrogenatoms are removed from a heterocyclic compound. The number of carbonatoms constituting the ring is usually about 3 to 60. A “divalent grouphaving a metal complex structure” is the remaining divalent group inwhich two hydrogen atoms are removed from the organic ligand of anorganic ligand-containing metal complex.

Specific examples of the trivalent aromatic group, trivalent grouphaving a metal complex, tetravalent aromatic group and the tetravalentgroup having a metal complex are as described above.

Preferable examples of the ring A and ring B include aromatichydrocarbon rings, and a benzene ring, naphthalene ring or anthracenering are even more preferable. The ring A and ring B also preferablyhave a substituent group.

A non-hydrogen group is connected to an end of the mono to tetravalentbonding group. Usually a linking group, dendritic structure, orbelow-described surface group are connected.

Preferable examples of X include —O—, —S—, —S(═O)—, —SO₂—, —P(R₄)—, and—PR₅(═O)—; and more preferable are —O— and —S—. Here, R₄ and R₅ are asdefined above.

Preferable examples of the above-described formula (6-1), formula (6-2)and formula (6-3) include the above-described A45 to A67, A79 to A85 andthe like.

Preferable examples of the above-described formula (7-1), formula (7-2),formula (7-3) and formula (7-4) include the above-described B25 to B44,B47 to B52, B55, B56, B60, B61 and the like.

The dendrimer compound of the present invention preferably has a metalcomplex structure. That is, at least one of the core unit (unit CA, unitCB unit CC or unit CD) and the unit in the dendritic structure (unit DAand/or unit DB) has a metal complex structure.

From the perspective of improving luminescence quantum efficiency, thecore unit (unit CA, unit CB unit CC or unit CD) preferably has a metalcomplex structure.

Preferable examples when the following group in formula (1),

has a metal complex structure include the above-described A38 to A44,A86 to A89, A112 to A116 and the like.

Preferable examples when the following group in formula (2),

has metal complex structure include the above-described B24, B57 to B64,B86 to B89 and the like.

“L” in formula (1), formula (2), formula (3) and formula (4) is a directbond or a linking group selected from the above-described (L-2).Preferred is a direct bond or a linking group selected from the divalentgroup represented by the below (L-2′). Even more preferred is a directbond.

Here, R₁′ is defined in the same manner as above.

The dendrimer compound of the present invention has a chemical structureformed by three-dimensionally repeating at least one dendritic structurerepresented by the formula (3) or (4) from a central core represented bythe formula (1) or (2). Examples of its terminal structure (hereinaftersometimes referred to as surface structures) include a hydrogen atom, ora group which forms the linking group described in the above L-2 from acondensation reaction or an addition reaction. Specific examples includea halogen atom, alkyl sulfonate group, aryl sulfonate group, arylalkylsulfonate group, boric acid group, borate ester group, sulfonium methylgroup, phosphonium methyl group, phosphonate methyl group,monohalogenated methyl group, formyl group, or the groups represented bythe below (L-3).

Alternatively, examples for the terminal structure include groupsrepresented by the above (L-3) which have further undergone acondensation reaction or an addition reaction. In this case, the residueobtained by removing, from a newly formed linking group, the linkinggroup to its terminal is called a surface group.

The terminal structure of the dendrimer compound of the presentinvention preferably has such a surface group. Specific examples of sucha surface group include an alkyl group, aryl group, alkoxy group,alkylthio group, aryloxy group, arylthio group, amino group, silylgroup, substituted silyl group, monovalent heterocyclic group,monovalent group having a metal complex structure, and a monovalentgroup having the structure represented by formula (5).

Examples of the monovalent group having a metal complex structureinclude those given below.

Examples of the monovalent group having a structure represented byformula (5) include the following.

In the above formula, R and X are defined in the same manner as above.

Next, a method for producing the dendrimer compound of the presentinvention will be explained.

Methods for producing the dendrimer can broadly be classified into twotypes. The first method is a method wherein a dendritic structurecomprising repeating units is repeated in three-dimensions around thecore acting as the center. The second method is a method for forming acore from a condensation reaction or an addition reaction ofmulti-branched compounds, which comprise a partial structure that formsa core from the condensation reaction or addition reaction, anddendrons, specifically, a chemical structure obtained bythree-dimensionally repeating a dendritic structure which comprisesbranched units.

The first production method will now be described in detail. A firstgeneration dendrimer compound can be produced from the condensationreaction or addition reaction of a compound represented by the followingformulas (8-1), (9-1), (8) or (9) with at least a compound selected fromthe compounds represented by formulas (10-1) and (11-1).

Here, unit CA, unit CB unit DA and unit DB are defined in the samemanner as above. Further, Y₁, Y₂ and YY₁ each independently representgroups which participate in the condensation reaction or additionreaction, and which satisfy the following conditions.

That is, with the combination of Y₁ and YY₁, a condensation reaction oraddition reaction occurs to form the above-described L. However, acondensation reaction or addition reaction does not occur with thecombination of Y₁ and Y₂.

Specific examples of Y₁, Y₂ and YY₁ include a halogen atom, alkylsulfonate group, aryl sulfonate group, arylalkyl sulfonate group, boricacid group, borate ester group, sulfonium methyl group, phosphoniummethyl group, phosphonate methyl group, formyl group, or the groupsrepresented by the below (L-3).

Here, examples of the alkyl sulfonate group include a methanesulfonategroup, ethanesulfonate group, trifluoromethanesulfonate group and thelike. Examples of the aryl sulfonate group include a benzenesulfonategroup, p-toluenesulfonate group and the like. Examples of the arylalkylsulfonate group include a benzyl sulfonate group and the like.

Examples of the borate ester group include the groups represented by thefollowing formula.

In the formula, Me represents a methyl group and Et represents an ethylgroup.

Examples of the sulfonium methyl group include the groups represented bythe following formulas.—CH₂S⁺Me₂X⁻, —CH₂S⁺Ph₂X⁻(wherein X represents a halogen atom, and Ph represents a phenyl group)

Examples of the phosphonium methyl group include the groups representedby the following formula.—CH₂P⁺Ph₃X⁻(wherein X represents a halogen atom)

Examples of the phosphonate methyl group include the groups representedby the following formula.—CH₂PO(OR₂′)₂(wherein X represents a halogen atom, R′ represents an alkyl group, arylgroup or arylalkyl group)

Following the production method of the above-described first generationdendrimer compound, a second generation dendrimer compound can beproduced by subjecting one or more compounds selected from the compoundsrepresented by the following formula (10-2) and formula (11-2) to acondensation reaction or addition reaction.

Here, unit DA and unit DB are defined in the same manner as above.Further, Y₃ and YY₂ each independently represent groups whichparticipate in the condensation reaction or addition reaction, and whichsatisfy the following conditions. That is, with the combination of Y₂and YY₂, or the combination of Y₃ and YY₁, a condensation reaction oraddition reaction occurs to form the above-described L. However, acondensation reaction or addition reaction does not occur with thecombination of Y₂ and Y₃. The specific examples of Y₃ and YY₂ are thesame as those described above.

A third generation dendrimer compound can also be obtained in the samemanner, by alternately subjecting in sequence one or more compoundsselected from the compounds represented by the above formula (10-1) andformula (11-1) to a condensation reaction or addition reaction with oneor more compounds selected from the compounds represented by the aboveformula (10-2) and formula (11-2).

The first method will now be schematically illustrated. The firstgeneration dendrimer represented by the following formula (18-10) can beobtained by subjecting a compound represented by the above formula (8)and a compound represented by the above formula (10-1) to a condensationreaction or addition reaction.

By further subjecting the compound represented by the above formula(10-2) to a condensation reaction or addition reaction, the secondgeneration dendrimer represented by the following formula (18-11) can beobtained.

By further subjecting the compound represented by the above formula(10-1) to a condensation reaction or addition reaction, the thirdgeneration dendrimer represented by the following formula (18-12) can beobtained.

A method separate from the first method will be explained in detailbelow. That is, instead of the compounds represented by the aboveformula (8) or formula (9), a first generation dendrimer can be obtainedby subjecting one or more compounds selected from the compoundsrepresented by the above formula (10-3) and formula (11-3) to acondensation reaction or addition reaction.

Here, unit DA and unit DB are defined in the same manner as above.Further, YY₁ is defined in the same manner as in formula (10-1). WhileY₄ does not directly react with YY₁, Y₄ is a group which will become aprecursor of the group which undergoes the condensation reaction oraddition reaction with YY₁. Specific examples of Y₄ include, when Y₁ isa hydroxyl group, a formyl group (oxidized to a carbonyl group) as acarboxyl group precursor which can undergo a condensation reaction withY₁, and a halogen atom (after reacting with a base, reacted withtrimethoxyborane) as a borate ester group precursor which can undergo acondensation reaction with Y₁. If Y₁ is a formyl group, further examplesinclude a monohalogenated methyl group as a precursor for a sulfoniummethyl group, phosphonium methyl group or phosphonate methyl group,which can undergo a condensation reaction with Y₁.

Subsequent to the production method of the above-described firstgeneration dendrimer compound, a second generation dendrimer compoundcan be obtained by converting Y₄ to a group for undergoing acondensation reaction or addition reaction with YY₁, and subjecting oneor more compounds selected from the compounds represented by the aboveformula (10-3) and formula (11-3) to a condensation reaction or additionreaction.

In the same manner, the third and following generations can be obtainedby converting to a group for undergoing a condensation reaction oraddition reaction with YY₁, and subjecting one or more compoundsselected from the compounds represented by the above formula (10-3) andformula (11-3) to a condensation reaction or addition reaction.

Specific examples of the second method include a method for synthesizinga dendrimer compound forming unit CA or unit CB by subjectingmulti-branched compounds, which comprise a chemical structureconstituted from at least one kind of dendritic structure selected fromthe dendritic structures represented by the following formula (12-1) orformula (12-2) and the above formula (3) and formula (4) being regularlyrepeated in three-dimensions, to a condensation reaction or an additionreaction.

Here, L is defined in the same manner as described above. Further PC1 isa partial structure wherein one kind or a plurality of kinds aresubjected to a condensation reaction or addition reaction, or arecoordinated onto a metal, to form unit CA or unit CB. Here, PC1 is apartial structure wherein one kind or a plurality of kinds arecoordinated onto a metal, to form unit CA or unit CB which comprise ametal complex structure. One kind or a plurality of kinds are subjectedto a condensation reaction or addition reaction to form a partialstructure forming unit CB.

More specifically, this is dendrimer synthesis method which uses thefollowing formula (12-3) or formula (12-4) as a starting material, toform unit CA or unit CB by condensing, adding or metal-coordinating amulti-branched compound obtained by alternately condensing or adding insequence one or more of the compounds selected from the compoundsrepresented by the above formulas (10-1) and (11-1) with one or more ofthe compounds selected from the compounds represented by the aboveformulas (10-2) and (11-2).

Here, unit Y₁, PC1 and PC2 are defined in the same manner as above.

Example of the following group in formula (12-1) and formula (12-3),

include the groups having the below acetylene skeleton forming a benzenering from trimerization by an addition reaction, or groups having thebelow ligand structure.

Here, Ar₈ represents a divalent group having a divalent aromatic ring ora metal complex, or a divalent group having the structure represented inthe above formula (5).

The second method will now be schematically illustrated. Themulti-branched compound represented by the following formula (18-13) canbe obtained with a compound represented by the above formula (12-3) as astarter material, by alternately subjecting compounds represented by theabove formula (10-1) and formula (10-2) to a condensation reaction oraddition reaction.

Next, the dendrimer compound represented by formula (18-12) is obtainedby subjecting the multi-branched compound represented by formula (18-13)to a condensation reaction, addition reaction or by coordinating onto ametal.

The first method is suitable for a production method of a dendrimercompound having the structure represented by formula (18-1), formula(18-2), formula (18-3), formula (18-4) and formula (18-7). The secondmethod is suitable for a production method of a dendrimer compoundhaving the structure represented by formula (18-5) and formula (18-6).

As the condensation reaction employed in the method for producing adendrimer compound of the present invention, commonly known condensationreactions can be used in accordance with the substituent group whichparticipates in the condensation reaction. If a double bond is formed inthe condensation reaction, the methods disclosed in JP-A-5-202355 can,for example, be used. That is, examples of such a method include aWittig reaction of a compound having a formyl group with a compoundhaving phosphonium methyl group, or a compound having a formyl group anda phosphonium methyl group; a Heck reaction of a compound having a vinylgroup with a compound having a halogen atom; a sulfonium-saltdecomposition method of a compound having two or more sulfonium methylgroups; and a McMurry reaction of a compound having two or more formylgroups and the like.

When forming the triple bond of the present invention, a Heck reaction,for example, can be utilized.

When the group participating in the condensation reaction is a halogenatom, alkyl sulfonate group, aryl sulfonate group, or arylalkylsulfonate group, examples of the condensation reaction include thoseconducted in the presence of a zero-valent nickel complex such as thatof the Yamamoto coupling reaction.

When one group participating in the condensation reaction is a halogenatom, alkyl sulfonate group, aryl sulfonate group, or arylalkylsulfonate group, and another group participating in the condensationreaction is boric acid or a borate group, examples of the condensationreaction include those conducted using a nickel catalyst or palladiumcatalyst such as that of the Suzuki coupling reaction.

Further examples include an esterification reaction, amidation reaction,or an etherification reaction of a boric acid group, borate ester groupor hydroxyl group.

Of the compounds represented by the above formula (8), formula (9),formula (10-1), formula (10-2), formula (11-1), and formula (11-2), acompound which comprises the structure represented by formula (5) is animportant raw material when producing the dendrimer compound of thepresent invention, especially when producing with the above-describedfirst production method. Such a compound is also effective as the rawmaterial for other multiply dendritic structures or compounds having amultiply dendritic structure.

As the addition reaction employed in the method for producing adendrimer compound of the present invention, commonly known additionreactions can be used in accordance with the substituent group whichparticipates in the condensation reaction. If one of the groups whichparticipates in the addition reaction is a hydrosilyl group, and theother is a vinyl group or a acetylene group, a hydrosilylation reactionusing a transition metal catalyst can be employed.

Preferable examples of such a compound include the compounds representedby following formula (6-4), formula (6-5), formula (6-6), formula (7-5),formula (7-6), formula (7-7) and formula (7-8).

The ring A, ring B and X are defined in the same manner as above. Inaddition, a preferable range is also the same as that described above.Ar₁, Ar₂, Ar₃, Ar₄, Ar₅, Ar₆, and Ar₇, “aa” and “bb” are also defined inthe same manner as above. YY is a halogen atom, alkyl sulfonate group,aryl sulfonate group, arylalkyl sulfonate group, boric acid group,borate ester group, sulfonium methyl group, phosphonium methyl group,phosphonate methyl group, monohalogenated methyl group, formyl group, ora group represented by the above (L-3).

The multi-branched compound, which comprises a chemical structureconstituted from at least one kind of dendritic structure selected fromthe dendritic structures represented by the above formula (12-1) orformula (12-2) and the above formula (3) and formula (4) being regularlyrepeated in three-dimensions, is an important raw material whenproducing the dendrimer compound of the present invention, especiallywhen producing with the above-described second production method. Such acompound is also effective as the raw material for other multiplydendritic structures or compounds having a multiply dendritic structure.

When a dendrimer compound of the present invention is used as an organicLED, its purity influences device performance, such as luminescencecharacteristics or the like. Therefore, it is preferable to use the rawmaterial compounds in dendrimer compound production after being purifiedby a method such as distillation, sublimation purification,re-crystallization or the like. Furthermore, after the dendrimercompound has been produced, it is preferable to conduct a purificationoperation of separation carried out by reprecipitation purification andchromatography.

Next, application of the dendrimer compound of the present inventionwill be explained.

The dendrimer compound of the present invention has fluorescence orphosphorescence in its solid state, and can be used as a luminescentbody (luminescent material).

This dendrimer compound also has excellent charge transport capacity,and can be preferably used as a material used in organic LEDs and as acharge transport material.

An organic LED which uses this dendrimer compound is a high performanceorganic LED which can be driven at a low-voltage and high-efficiency.

Therefore, such an organic LED can be preferably used for the back lightof a liquid crystal display, a curved or planar light source forlighting, a segment type display device, and an apparatus such as a dotmatrix flat panel display.

Moreover, the dendrimer compound of the present invention can also beused as a laser dye, a material used in organic solar cells, an organicsemiconductor used for organic transistors, and conductive thin filmmaterials such as luminescent thin films, conductive thin films, organicsemiconductor thin films and the like.

Next, the organic LED of the present invention will be explained.

The organic LED of the present invention comprises an organic layerbetween electrodes consisting of an anode and a cathode, wherein theorganic layer comprises the dendrimer compound of the present invention.

The organic layer may be any of a luminescent layer, a hole transportinglayer, and an electron transport layer, although it is preferable thatthe organic layer is a luminescent layer.

Here, a “luminescent layer” means a layer having a function of emittinglight, “hole transporting layer” means a layer having a function oftransporting holes, and “electron transport layer” means a layer havinga function of transporting electrons. The electron transport layer andthe hole transporting layer are collectively referred to as “chargetransport layer”. Two or more layers of the luminescent layer, holetransporting layer, and electron transport layer can be used eachindependently.

When an organic layer is the luminescent layer, such an organicluminescent layer may further contain a hole transport material, anelectron transport material, or a luminescent material. Here, a“luminescent material” means a material which exhibits fluorescenceand/or phosphorescence. Moreover, a conjugated polymer having anaromatic ring on its main chain can also be contained.

When mixing the dendrimer compound of the present invention with a holetransport material, the mixing ratio of the hole transport material is 1wt % to 80 wt % of the total amount of the mixture, and is preferably 5wt % to 60 wt %. When mixing the dendrimer compound of the presentinvention with an electron transport material, the mixing ratio of theelectron transport material is 1 wt % to 80 wt % of the total amount ofthe mixture, and is preferably 5 wt % to 60 wt %. Furthermore, whenmixing the dendrimer compound of the present invention with aluminescent material, the mixing ratio of the luminescent material is 1wt % to 80 wt % of the total amount of the mixture, and is preferably 5wt % to 60 wt %. When mixing the dendrimer compound of the presentinvention with a luminescent material, a hole transport material, and/oran electron transport material, the mixing ratio of the luminescentmaterial is 1 wt % to 50 wt % of the total amount of the mixture, andpreferably 5 wt % to 40 wt %, in which the total amount of the holetransport material and the electron transport material is 1 wt % to 50wt %, and preferably 5 wt % to 40 wt %. The content of the dendrimercompound of the present invention is 99 wt % to 20 wt %. While themixing ratio in the composition consisting of the dendrimer compound ofthe present invention and the conjugated polymer may be determined so asto attain optimum film forming properties and luminescencecharacteristics, the mixing ratio of the conjugated polymer is 10 wt %to 99 wt % of the total amount of the mixture, and is preferably 10 wt %to 90 wt %.

As the hole transport material, electron transport material, luminescentmaterial, and conjugated polymer to be mixed, known low molecular weightcompounds and known polymer compounds can be used, although it ispreferable to use known polymer compounds. Examples of hole transportmaterials, electron transport materials or luminescent materialsconsisting of a polymer compound include: the polyfluorene andderivatives and copolymers thereof; polyarylene and derivatives andcopolymers thereof; polyarylene vinylene and derivatives and copolymersthereof; and (co)polymer of an aromatic amine and derivatives thereofdisclosed in WO 99/13692, WO 99/48160, GB 2340304A, WO 00/53656, WO01/19834, WO 00/55927, GB 2348316 and WO 00/46321, WO 00/06665, WO99/54943, WO 99/54385, U.S. Pat. No. 5,777,070 and WO 98/06773, WO97/05184, WO 00/35987, WO 00/53655, WO 01/34722, WO 99/24526, WO00/22027, WO 00/22026, WO 98/27136, US 573636 and WO 98/21262, U.S. Pat.No. 5,741,921, WO 97/09394, WO 96/29356, WO 96/10617, EP 0707020 and WO95/07955, JP-A-2001-181618, JP-A-2001-123156, JP-A-2001-3045,JP-A-2000-351967, JP-A-2000-303066, JP-A-2000-299189, JP-A-2000-252065,JP-A-2000-136379, JP-A-2000-104057, JP-A-2000-80167, JP-A-10-324870,JP-A-10-114891, JP-A-9-111233, JP-A-9-45478, and the like.

Examples of fluorescent materials consisting of a low molecular weightcompound include: naphthalene derivatives; anthracene and derivativesthereof, and derivatives thereof; perylene and derivatives thereof;dyes, such as polymethines, xanthenes, coumarins, and cyanines;8-hydroxyquinoline or a metal complex of its derivatives; aromaticamines; tetraphenylcyclopentadienes or its derivatives;tetraphenylbutadiene or its derivatives, and the like.

Specific examples of compounds that can be used include known materials,such as those disclosed in JP-A-57-51781 or JP-A-59-194393.

The polymer portion of the polymer compound, which is characterized bythe dendrimer compound of the present invention being bound with aconstituent atom in the main chain structure or side chain of thepolymer compound, is preferably the same compound as the known polymercompounds illustrated above.

Examples of phosphorescent compounds consisting of a low molecularweight compound include triplet luminescence complexes such as: Ir(ppy)₃and Btp₂Ir(acac) which have iridium as a central metal; PtOEP which hasplatinum as a central metal; and Eu(TTA)3phen which has europium as acentral metal, and the like.

Specific examples of triplet luminescence complexes are disclosed in:Nature, (1998), 395, 151, Appl. Phys. Lett. (1999), 75(1), 4, Proc.SPIE-Int. Soc. Opt. Eng. (2001), 4105 (Organic Light-Emitting Materialsand Devices IV), 119, J. Am. Chem. Soc., (2001), 123, 4304, Appl. Phys.Lett., (1997), 71(18), 2596, Syn. Met., (1998), 94(1), 103, Syn. Met.,(1999), 99(2), 1361, Adv. Mater., (1999), 11(10), 852, Jpn. J. Appl.Phys., 34, 1883 (1995).

Preferable examples of dendrimer compounds which are mixed with tripletluminescence complexes include, in the structure represented by formula(5), those having only a structure wherein X is —O—, those having only astructure wherein X is —S—, and those having only a structure wherein Xis —O— and X is —S—, because their phosphorescence can be effectivelyutilized and because light emission quantum efficiency is improved.

The composition of the present invention comprises at least one kind ofmaterial selected from a hole transport material, an electron transportmaterial, and a luminescent material, and the dendrimer compound of thepresent invention, and can be used for a luminescent material or acharge transport material. The composition of the present invention maycontain two or more of the dendrimer compound of the present invention.

The content ratio of the at least one kind of material selected from ahole transport material, an electron transport material, and aluminescent material, with the dendrimer compound of the presentinvention can be determined according to the intended use. When used asa luminescent material, the content ratio is preferably the same as thatof the above-described luminescent layer.

Regarding the thickness of the luminescent layer in the organic LED ofthe present invention, its optimum value depends on the material used,and may properly be selected so that the driving voltage and the lightemitting efficiency are a suitable value. The thickness is, for example,from 1 nm to 1 μm, preferably from 2 nm to 500 nm, further preferablyfrom 5 nm to 200 nm.

Examples of methods for forming the luminescent layer include methodsconducted using film formation from a solution. Examples of film-formingmethods from a solution include application methods, such as a spin coatmethod, casting method, microgravure coating method, gravure coatingmethod, bar-coating method, roll coating method, wire bar coat method,dip coat method, spray coating method, screen printing, flexographymethod, offset printing, and ink jet printing method, and the like.Printing methods, such as screen printing, flexography method, offsetprinting, and ink jet printing method, are preferable, since patternforming and multicolored printing are easy.

As the ink composition used for the printing method or similar method,at least 1 kind of the dendrimer compound of the present inventionshould be contained, and additives, such as a hole transport material,electron transport material, luminescent material, solvent, orstabilizer, may be contained in addition to the dendrimer compound ofthe present invention.

The ratio of the dendrimer compound of the present invention in the inkcomposition is 20 wt % to 100 wt % of the total weight of thecomposition except the solvent, and preferably 40 wt % to 100 wt %.

When a solvent is contained in the ink composition, the ratio of thesolvent is 1 wt % to 99.9 wt % of the total weight of the composition,preferably 60 wt % to 99.5 wt %, and more preferably 80 wt % to 99.0 wt%.

Although a suitable viscosity of the ink composition depends on theprinting method, when an ink jet printed or similar ink composition isprocessed via a discharging apparatus, in order to prevent clogging andcurved flight at discharge, the viscosity is preferably in a range of 1to 20 mPa·s at 25° C.

The solvent used as the ink composition is not especially limited, andpreferable are those which can dissolve or uniformly disperse thematerials constituting the ink composition other than the solvent. Whenthe materials constituting the ink composition are soluble in a nonpolarsolvent, examples of the solvent include: chlorinated solvents, such aschloroform, methylene chloride, and dichloroethane; ether solvents, suchas tetrahydrofuran; aromatic hydrocarbon solvents, such as toluene, andxylene; ketone solvents, such as acetone, and methyl ethyl ketone; andester solvents, such as ethyl acetate, butyl acetate, and ethylcellosolve acetate.

Moreover, examples of the organic LED of the present invention include:an organic LED having an electron transport layer disposed between acathode and a luminescent layer; an organic LED having a holetransporting layer disposed between an anode and a luminescent layer;and an organic LED having an electron transport layer disposed between acathode and a luminescent layer, and a hole transporting layer disposedbetween an anode and a luminescent layer.

For example, the following structures a) to d) are specific examples.

a) anode/luminescent layer/cathode

b) anode/hole transporting layer/luminescent layer/cathode

c) anode/luminescent layer/electron transport layer/cathode

d) anode/hole transporting layer/luminescent layer/electron transportlayer/cathode (wherein, “/” indicates adjacent lamination of layers.Hereinafter, the same)

When the organic LED of the present invention has a hole transportinglayer, examples of hole transport materials which can be used includepolyvinylcarbazole or derivatives thereof, polysilane or derivativesthereof, polysiloxane derivatives having an aromatic amine in a sidechain or main chain, pyrazoline derivatives, arylamine derivatives,stilbene derivatives, triphenyldiamine derivatives, polyaniline orderivatives thereof, polythiophene or derivatives thereof, polypyrroleor derivatives thereof, poly(p-phenylenevinylene) or derivativesthereof, poly(2,5-thienylenevinylene) or derivatives thereof, and thelike.

Specific examples of the hole transport material include those describedin JP-A-63-70257, JP-A-63-175860, JP-A-2-135359, JP-A-2-135361,JP-A-2-209988, JP-A-3-37992 and JP-A-3-152184.

Among them, preferable examples of the hole transport material used inthe hole transporting layer include polymer hole transport materials,such as polyvinylcarbazole or derivatives thereof, polysilane orderivatives thereof, polysiloxane derivatives having an aromatic aminecompound group in a side chain or main chain, polyaniline or derivativesthereof, polythiophene or derivatives thereof, poly(p-phenylenevinylene)or derivatives thereof, poly(2,5-thienylenevinylene) or derivativesthereof, or the like, and further preferable are polyvinylcarbazole orderivatives thereof, polysilane or derivatives thereof and polysiloxanederivatives having an aromatic amine compound group in a side chain ormain chain.

Moreover, examples of a hole transport material consisting of a lowmolecular weight compound include pyrazoline derivatives, arylaminederivatives, stilbene derivatives, and triphenyl diamine derivatives. Inthe case of a low molecular weight hole transport material, it ispreferably used by dispersing in a polymer binder.

As the polymer binder to be mixed, preferable are those which do notinhibit charge transportation to an extreme extent, and do not havestrong absorbance of visible light. Examples of such polymer bindersinclude: poly(N-vinylcarbazole); polyaniline or derivatives thereof;polythiophene or derivatives thereof; poly(p-phenylenevinylene) orderivatives thereof; poly(2,5-thienylenevinylene) or derivativesthereof; polycarbonate; polyacrylate, poly methylacrylate,polymethylmethacrylate, polystyrene, polyvinylchloride, polysiloxane,and the like.

Polyvinyl carbazole and derivatives thereof can be obtained from, forexample, a vinyl monomer, by cationic polymerization or radicalpolymerization.

Examples of polysilane or derivatives thereof include the compoundsdescribed in Chem. Rev., 89, 1359 (1989) and GB 2300196 publishedspecification, and the like. The methods described in these documentscan be used for the synthesis method, although it is especiallypreferable to use the Kipping method.

As the polysiloxane or derivatives thereof, compounds which can bepreferably used include those having the structure of theabove-described low molecular weight hole transport material in a sidechain or main chain, since the siloxane skeleton structure has poor holetransportation. Particularly preferable examples include compoundshaving a hole transporting aromatic amine in their side chain or mainchain.

The method for forming a hole transporting layer is not limited. In thecase of a low molecular weight hole transporting layer, examples includea method in which the layer is formed from a mixed solution with apolymer binder. In the case of a polymer hole transport material,examples include a method in which the layer is formed from a solution.

The solvent used for film formation from solution is not particularlylimited, providing it can dissolve a hole transport material. Examplesof such solvent include chlorinated solvents such as chloroform,methylene chloride, dichloroethane and the like, ether solvents such astetrahydrofuran and the like, aromatic hydrocarbon solvents such astoluene, xylene and the like, ketone solvents such as acetone, methylethyl ketone and the like, and ester solvents such as ethyl acetate,butyl acetate, ethylcellosolve acetate and the like.

Examples of the film forming method from solution which can be usedinclude coating methods from a solution, such as a spin coating method,casting method, microgravure coating method, gravure coating method, barcoating method, roll coating method, wire bar coating method, dipcoating method, spray coating method, screen printing method,flexography method, offset printing method, inkjet printing method andthe like.

Regarding the thickness of the hole transporting layer, the optimumvalue depends on the material used, and may properly be selected so thatthe driving voltage and the light emitting efficiency are an optimumvalue. The thickness should be at least such that pinholes are notgenerated, but not so thick as to undesirably increase the drivingvoltage of a device. Therefore, the film thickness of the holetransporting layer is, for example, from 1 nm to 1 μm, preferably 2 nmto 500 nm, and more preferably 5 nm to 200 nm.

When the organic LED of the present invention has an electron transportlayer, known compounds can be used as the electron transport material.Examples include oxadiazole derivatives, anthraquinodimethane orderivatives thereof, benzoquinone or derivatives thereof, naphthoquinoneor derivatives thereof, anthraquinone or derivatives thereof,tetracyanoanthraquinodimethane or derivatives thereof, fluorenonederivatives, diphenyldicyanoethylene or derivatives thereof,diphenoquinone derivatives, or metal complexes of 8-hydroxyquinoline orderivatives thereof, polyquinoline and derivatives thereof,polyquinoxaline and derivatives thereof, polyfluorene or derivativesthereof, and the like.

Specific examples include the compounds described in JP-A-63-70257,JP-A-63-175860, JP-A-2-135359, JP-A-2-135361, JP-A-2-209988,JP-A-3-37992, JP-A-3-152184, and the like.

Among them, preferable are oxadiazole derivatives, benzoquinone orderivatives thereof, anthraquinone or derivatives thereof, or metalcomplexes of 8-hydroxyquinoline or derivatives thereof, polyquinoline orderivatives thereof, polyquinoxaline or derivatives thereof, andpolyfluorene or derivatives thereof, and further preferable are2-(4-biphenyl)-5-(4-t-butylphenyl)-1,3,4-oxadiazole, benzoquinone,anthraquinone, tris(8-quinolinol) aluminum and polyquinoline.

The method for forming the electron transport layer is not particularlylimited. In the case of a low molecular weight electron transportmaterial, examples include a vapor deposition method from powder, or amethod of film-forming from solution or melted state. In the case of ahigh molecular weight electron transport material, examples include amethod of film-forming from solution or melted state. When performingfilm formation from solution or molten state, the above polymer bindercan be used together therewith.

The solvent used in film formation from solution is not particularlylimited, provided it can dissolve the electron transport material and/orpolymer binder. Examples of such a solvent include chlorinated solventssuch as chloroform, methylene chloride, dichloroethane and the like,ether solvents such as tetrahydrofuran and the like, aromatichydrocarbon solvents such as toluene, xylene and the like, ketonesolvents such as acetone, methyl ethyl ketone and the like, and estersolvents such as ethyl acetate, butyl acetate, ethylcellosolve acetateand the like.

Examples of the film forming method from solution or melted state whichcan be used include coating methods such as a spin coating method,casting method, microgravure coating method, gravure coating method, barcoating method, roll coating method, wire bar coating method, dipcoating method, spray coating method, screen printing method,flexography method, offset printing method, inkjet printing method andthe like.

Regarding the thickness of the electron transport layer, the optimumvalue depends on the material used, and may properly be selected so thatthe driving voltage and the light emitting efficiency are an optimumvalue. The thickness should be at least such that pinholes are notgenerated, but not so thick as to undesirably increase the drivingvoltage of a device. Therefore, the film thickness of the holetransporting layer is, for example, from 1 nm to 1 μm, preferably 2 nmto 500 nm, and more preferably 5 nm to 200 nm.

Among charge transport layers provided adjacent to an electrode, thosehaving a function to improve the charge injection efficiency from theelectrode and to lower the driving voltage of a device are sometimescommonly called charge injection layers (hole injection layer, electroninjection layer) particularly.

To enhance adherence with an electrode and improving charge injectionfrom an electrode, the above-described charge injection layer orinsulation layer having a thickness of 2 nm or less may also be providedadjacent to an electrode, and further, for enhancing adherence of theinterface, preventing mixing and the like, a thin buffer layer may alsobe inserted into the interface of a charge transport layer andluminescent layer.

The order and number of layers laminated and the thickness of each layercan be appropriately applied while considering light emitting efficiencyand life of the device.

In the present invention, examples of an organic LED provided with acharge injection layer (electron injection layer, hole injection layer)include organic LEDs provided with the charge injection layer adjacentto the cathode and organic LEDs provided with a charge injection layeradjacent to the anode.

Specific examples include the following structures e) to p), forexample.

e) anode/charge injection layer/luminescent layer/cathode

f) anode/luminescent layer/charge injection layer/cathode

g) anode/charge injection layer/luminescent layer/charge injectionlayer/cathode

h) anode/charge injection layer/hole transporting layer/luminescentlayer/cathode

i) anode/hole transporting layer/luminescent layer/charge injectionlayer/cathode

j) anode/charge injection layer/hole transporting layer/luminescentlayer/charge injection layer/cathode

k) anode/charge injection layer/luminescent layer/electron transportlayer/cathode

l) anode/luminescent layer/electron transport layer/charge injectionlayer/cathode

m) anode/charge injection layer/luminescent layer/electron transportlayer/charge injection layer/cathode

n) anode/charge injection layer/hole transporting layer/luminescentlayer/electron transport layer/cathode

o) anode/hole transporting layer/luminescent layer/electron transportlayer/charge injection layer/cathode

p) anode/charge injection layer/hole transporting layer/luminescentlayer/electron transport layer/charge injection layer/cathode

Specific examples of the charge injection layer include: layerscontaining a conductive polymer; layers which are disposed between ananode and a hole transporting layer and which contain a material havingan ionization potential between that of the anode material and the holetransport material contained in the hole transporting layer; and layerswhich are disposed between a cathode and an electron transport layer andwhich contain a material having an electron affinity between that of thecathode material and the electron transport material contained in theelectron transport layer, and the like.

When the above-described charge injection layer is a layer containing aconductive polymer, the electric conductivity of the conductive polymeris preferably 10⁻⁵ S/cm or more and 10³ S/cm or less, and for decreasingthe leak current between light emitting pixels, more preferably 10⁻⁵S/cm or more and 10² S/cm or less, further preferably 10⁻⁵ S/cm or moreand 10¹ S/cm or less.

Usually, in order to make the electrical conductivity of the conductivepolymer 10⁻⁵ S/cm or more and 10³ S/cm or less, ions are doped into theconductive polymer in an appropriate quantity.

Regarding the kinds of ions to be doped, anions are used for a holeinjection layer and cations are used for an electron injection layer.Examples of anions include a polystyrenesulfonate ion,alkylbenzenesulfonate ion, camphor sulfonate ion and the like. Examplesof cations include a lithium ion, sodium ion, potassium ion, tetrabutylammonium ion and the like.

The thickness of the charge injection layer is for example, from 1 nm to100 nm, and is preferably from 2 nm to 50 nm.

Materials used as the charge injection layer can be appropriatelyselected in view of their relationship with the electrode or material ofthe adjacent layer. Examples include conductive polymers, such aspolyaniline and derivatives thereof, polythiophene and derivativesthereof, polypyrrole and derivatives thereof, polyphenylenevinylene andderivatives thereof, polythienylenevinylene and derivatives thereof,polyquinoline and derivatives thereof, polyquinoxaline and derivativesthereof, and polymers which contain an aromatic amine structure in amain chain or side chain, metal phthalocyanines (e.g. copperphthalocyanine and the like), carbon, and the like.

The insulation layer having a thickness of 2 nm or less has a functionof facilitating charge injection. Examples of the material for theinsulating layer include a metal fluoride, metal oxide, organicinsulating material, and the like. Examples of organic LEDs having a 2nm thick or less insulation layer include an organic LED containing aninsulation layer having a thickness of 2 nm or less adjacent to thecathode, and an organic LED containing an insulation layer having athickness of 2 nm or less adjacent to the anode.

Specific examples include the following structures q) to ab), forexample.

q) anode/insulation layer having a thickness of 2 nm or less/luminescentlayer/cathode

r) anode/luminescent layer/insulation layer having a thickness of 2 nmor less/cathode

s) anode/insulation layer having a thickness of 2 nm or less/luminescentlayer/insulation layer having a thickness of 2 nm or less/cathode

t) anode/insulation layer having a thickness of 2 nm or less/holetransporting layer/luminescent layer/cathode

u) anode/hole transporting layer/luminescent layer/insulation layerhaving a thickness of 2 nm or less/cathode

v) anode/insulation layer having a thickness of 2 nm or less/holetransporting layer/luminescent layer/insulation layer having a thicknessof 2 nm or less/cathode

w) anode/insulation layer having a thickness of 2 nm or less/luminescentlayer/electron transport layer/cathode

x) anode/luminescent layer/electron transport layer/insulation layerhaving a thickness of 2 nm or less/cathode

y) anode/insulation layer having a thickness of 2 nm or less/luminescentlayer/electron transport layer/insulation layer having a thickness of 2nm or less/cathode

z) anode/insulation layer having a thickness of 2 nm or less/holetransporting layer/luminescent layer/electron transport layer/cathode

aa) anode/hole transporting layer/luminescent layer/electron transportlayer/insulation layer having a thickness of 2 nm or less/cathode

ab) anode/insulation layer having a thickness of 2 nm or less/holetransporting layer/luminescent layer/electron transport layer/insulationlayer having a thickness of 2 nm or less/cathode

The substrate forming the organic LED of the present invention should bea substrate that does not change during formation of the electrodes ororganic layer. Examples include glass, plastic, polymer film, siliconsubstrates and the like. In the case of an opaque substrate, it ispreferable that the opposite electrode is transparent orsemitransparent.

Usually, at least one of the anode or the cathode in the organic LED ofthe present invention is transparent or semitransparent. It ispreferable that the anode side is transparent or semitransparent.

Conductive metal oxide films, semitransparent metal thin films and thelike can be used as the material for such an anode. Specific examples ofmaterials that can be used include indium oxide, zinc oxide, tin oxide,and films (NESA and the like) fabricated by using a conductive glasscomposed of indium-tin oxide (ITO), indium-zinc oxide and the like,which are complexes of the above materials, and gold, platinum, silver,copper and the like. Among them, ITO, indium-zinc oxide, and tin oxideare preferable. Examples of the fabricating method include a vacuumvapor deposition method, sputtering method, ion plating method, platingmethod and the like. Organic transparent conductive films can be used asthe anode, such as polyaniline or derivatives thereof, polythiophene orderivatives thereof and the like.

The thickness of the anode can be appropriately selected taking intoconsideration light transmission characteristics and the degree ofelectric conductivity, and can be, for example, from 10 nm to 10 μm,preferably from 20 nm to 1 μm, and more preferably from 50 nm to 500 nm.

Further, to facilitate charge injection, the anode can be provided witha layer comprising a phthalocyanine derivative, a conductive polymer,carbon or the like, or a layer having an average film thickness of 2 nmor less comprising a metal oxide, metal fluoride, organic insulatingmaterial or the like.

A material having a low work function is preferable as the cathodematerial used in the organic LED of the present invention. Examplesinclude metals such as lithium, sodium, potassium, rubidium, cesium,beryllium, magnesium, calcium, strontium, barium, aluminum, scandium,vanadium, zinc, yttrium, indium, cerium, samarium, europium, terbium,ytterbium and the like; alloys comprising two of more of these metals;alloys comprising one or more of these metals with one or more of gold,silver, platinum, copper, manganese, titanium, cobalt, nickel, tungstenand tin; graphite or graphite intercalation compounds and the like.Examples of alloys include a magnesium-silver alloy, magnesium-indiumalloy, magnesium-aluminum alloy, indium-silver alloy, lithium-aluminumalloy, lithium-magnesium alloy, lithium-indium alloy, calcium-aluminumalloy and the like. The cathode may be formed into a laminated structureof two or more layers.

The thickness of the cathode can be appropriately selected taking intoconsideration light transmission characteristics and the degree ofelectric conductivity, and can be, for example, from 10 nm to 10 μm,preferably from 20 nm to 1 μm, and more preferably from 50 nm to 500 nm.

Examples of the method for fabricating the cathode include a vacuumvapor deposition method, sputtering method, lamination method in which ametal thin film is adhered under heat and pressure, and the like.Further, between the cathode and the organic layer, there may also beprovided a layer comprising a conductive polymer, or a layer having anaverage film thickness of 2 nm or less comprising a metal oxide, metalfluoride, organic insulation material and the like. After fabrication ofthe cathode, a protective layer may also be provided which protects theorganic LED. For stable long term use of the organic LED, it ispreferable to provide a protective layer and/or protective cover forprotection of the device in order to prevent it from external damage.

For this protective layer, materials that can be used include polymercompounds, metal oxides, metal fluorides, metal borides and the like.For the protective cover, materials that can be used include glassplate, plastic plate whose surface has been subjected to alow-water-permeation treatment, and the like. A preferable method thatcan be used seals by pasting the cover with a device substrate using aheat curing resin or photocuring resin. If space is maintained using aspacer, it is easy to prevent a device from being damaged. By fillingthis space with an inert gas such as nitrogen or argon, it is possibleto prevent oxidation of the cathode. In addition, by placing a desiccantsuch as barium oxide or the like in the above-described space, it iseasy to suppress damage to a device from moisture adhered in theproduction process. It is preferable to adopt any one or more of thesemeasures.

The organic LED of the present invention can be used as a planar lightsource, segment display device, dot matrix display device, and backlight of a liquid crystal display.

To achieve a planar light emission using the organic LED of the presentinvention, a planar anode and cathode can be placed so that they overlapeach other. Further, to achieve a patterned light emission, methodswhich can be used include: a method which places a mask provided with apatterned window on the above-described planar light emitting device; amethod which essentially effects non-light emission by forming anextremely thick non-luminescent portion organic layer; and a methodwhich forms either the anode or the cathode, or both electrodes, in apattern. By using any of these methods to form a pattern, and by placingsome electrodes so that they can be independently turned on/off, asegment type display device can be obtained which is capable ofdisplaying digits, letters, simple marks and the like. Further, to forma dot matrix device, the anodes and cathodes can be placed in a stripedmanner so as to cross at right angles. Area color displays and multicolor displays are made possible from a method in which a plurality ofkinds of polymer compounds emitting different colors of lights areplaced separately or a method in which a color filter or luminescenceconverting filter is used. A dot matrix display can be driven by passivedriving, or by active driving combined with TFT and the like. Thesedisplay devices can be used as a display of a computer, television,portable terminal, portable telephone, car navigation, view finder of avideo camera, and the like.

Further, the above-described planar light emitting device is thin andself-light-emitting, and can be suitably used as a planar light sourcefor backlight of a liquid crystal display, or as a planar light sourcefor illumination. Further, if a flexible plate is used, it can also beused as a curved light source or a display.

The following examples further illustrate the present invention indetail but do not limit the scope thereof.

Example 1 Synthesis of Intermediate D

Under an argon atmosphere, raw material A (1 g, 1.7 mmol), raw materialB (0.861 g, 1.8 mmol), and bis(triphenylphosphine)palladium (II)dichloride (65 mg, 0.09 mmol) were weighed out and charged into a 100 mLthree-necked flask, and anhydrous THF (20 mL) was charged into thismixture. The resulting solution was cooled with ice. Once the solutionwas sufficiently cooled, 3M aqueous sodium hydroxide (5 mL) was chargedthereto under stirring. While cooling with ice, the solution was cooledfor 7 hours, after which water and chloroform were added and thesolution separated out. The organic layer was separated with brine, andthen dried using sodium sulfate. The drying agent was filtered off, andthe solvent was removed by distillation, whereby intermediate D (570 mg,39.7%) was obtained as a white solid by silica gel chromatography.

¹H-NMR (300 MHz/CDCl₃): δ7.99 (s, 1H), 7.82-7.80 (m, 4H), 7.66-7.60 (m,5H), 7.55-7.48 (m, 5H), 4.22-4.13 (m, 4H), 1.97-1.81 (m, 4H), 1.60-1.55(m, 6H), 1.38 (s, 18H), 1.32-1.20 (m, 12H), 0.87-0.82 (m, 8H)

Raw material A was synthesized in accordance with a method disclosed inJP-A-2004-043544, and raw material B was synthesized in accordance witha method disclosed in WO 02/066552.

Synthesis of Intermediate E

Under an argon atmosphere, raw material D (265 mg, 0.31 mmol) wasweighed out and charged into a 100 mL three-necked flask, and THF (10mL) was charged thereto. The resulting solution was cooled to −78° C.,and then dropped with a n-BuLi hexane solution (2.4 M, 0.17 mL, 0.40mmol). Once the dropping was finished, the resulting solution wasstirred for 15 minutes with the temperature being held at the abovelevel. Isopropoxypinacol borane (0.07 g, 0.04 mmol) was added thereto,and the mixture was stirred at −78° C. for 4 hours. This reactionsolution was quenched with water. The resulting solution was chargedwith chloroform and the organic layer was separated out. The organiclayer was further separated with brine, and then dried using sodiumsulfate. The drying agent was filtered off, and then the solvent wasremoved by distillation under reduced pressure, whereby a crude refinedproduct was obtained. This compound was used in the following reactionwithout undergoing the above-described purification.

¹H-NMR (300 MHz/CDCl₃): δ8.10 (s, 1H), 7.86-7.79 (m, 4H), 7.66-7.63 (m,5H), 7.50-7.47 (m, 5H), 4.19-4.10 (m, 4H), 1.90-1.80 (m, 4H), 1.62-1.56(m, 6H), 1.55 (s, 12H), 1.38 (s, 18H), 1.33-1.20 (m, 12H), 0.90-0.82 (m,8H)

Synthesis of Dendrimer F

Under an argon atmosphere, intermediate C (50 mg, 0.06 mmol), compound E(340 mg) and bis(triphenylphosphine)palladium (II) dichloride (30 mg,0.04 mmol) were weighed out and charged into a 100 mL three-neckedflask, and the resulting mixture was charged with THF (10 mL). Thissolution was charged with aqueous tetraethylammonium hydroxide (1.3 mL),and the resulting solution was heated to reflux. Once the reaction wasfinished, water and chloroform were added and the solution separatedout. The organic layer was separated with brine, and then dried usingsodium sulfate. After filtering, the solvent was removed by distillationunder reduced pressure, whereby dendrimer F (80 mg) was obtained byseparating using silica gel chromatography. This dendrimer F alsocontained compound F-1 and compound F-2.

MALDI TOF-MS:

M/Z=2991 (M⁺, dendrimer F), 2291 (M⁺, compound F-1), 1591 (M⁺, compoundF-2)

Intermediate C was obtained by brominatingfac-tris-(2-(phenyl)pyridinato,N,C^(2′))iridium (III) by a commonbrominating method of an aromatic organic compound.

¹H-NMR (300 MHz/CDCl₃): δ7.85 (d, J=8.1 Hz, 3H), 7.74 (t, J=7.8 Hz, 3H),7.48 (d, J=9 Hz, 3H), 7.47 (d, J=4.8 Hz, 3H), 6.98-6.90 (m, 6H) 6.66 (d,J=8.1 Hz, 3H)

Example 2

A 1.0 wt % by weight chloroform solution of the dendrimer F obtained inExample 1 was prepared.

On a glass substrate which had a 150 nm thick ITO film deposited bysputtering, a 50 nm thick film was formed by spin coating using asolution of poly(ethylenedioxythiophene)/polystyrene sulfonic acid(BaytronP, Bayer) and dried for 10 minutes on a hot plate at 200° C.Next, a film was formed by spin coating at a revolution rate of 1,500rpm using the above-prepared chloroform solution. The film thickness wasabout 80 nm. The film was dried under reduced pressure at 80° C. for 1hour. The dried film was then subjected to vapor deposition to formabout 4 nm of LiF as the cathode buffer layer, and about 5 nm of calciumfollowed by about 80 nm of aluminum as the cathode, to thereby fabricatean EL device. It should be noted that the metal vapor deposition wasstarted after the degree of vacuum had reached 1×10⁻⁴ Pa or below. Whenvoltage was applied to the thus-obtained device, EL luminance wasobtained with a peak at 515 nm.

Example 3

A 1.0 wt % by weight chloroform solution of the dendrimer F obtained inExample 1 was prepared in which 20 wt. % of the below compound 2 hadbeen added. Using this solution, an EL device was obtained in the samemanner as that described for Example 2. Spin coating of the solution wasperformed at 3,000 rpm, and the film thickness was about 85 nm. Whenvoltage was applied to the thus-obtained device, EL luminance wasobtained with a peak at 515 nm. The device exhibited a luminance of 100cd/m² at 12.4 V. Maximum luminance efficiency was 0.63 cd/A. Compound 2was purchased from Aldrich.

Example 4 Synthesis of Dendrimer G

The byproducts obtained during the synthesis of intermediate D wereseparated by silica gel chromatography, and then recrystallized from achloroform/acetonitrile solution, whereby 180 mg of dendrimer G wasisolated.

¹H-NMR (300 MHz/CDCl₃): δ7.88-7.68 (m, 8H), 7.68-7.65 (m, 10H),7.51-7.48 (m, 8H), 4.19 (t, J=5.7 Hz, 4H), 1.60-1.55 (m, 6H), 1.38 (s,18H), 1.29-1.21 (m, 22H), 0.87-0.82 (m, 8H)

Example 5

A 1.0 wt % by weight chloroform solution of the dendrimer G obtained inExample 4 was prepared.

Using this solution, an EL device was obtained in the same manner asthat described for Example 2. Spin coating of the solution was performedat 3,000 rpm, and the film thickness was about 100 nm. When voltage wasapplied to the thus-obtained device, EL luminance was obtained with apeak at 400 nm.

The invention claimed is:
 1. An ink composition characterized bycomprising a dendrimer compound characterized by comprising a corerepresented by the following formula (1-2) and at least one dendriticstructure selected from dendritic structures represented by thefollowing formula (3) or (4):

wherein unit CD represents a structure represented by the followingformula (5):

wherein a ring A and a ring B each independently represent an aromaticring, X represents —O—, —S—, —S(═O)—, —SO₂—, —B(R₁)—, —Si(R₂)(R₃)—,—P(R₄)— or —PR₅(═O)—, and R₁, R₂, R₃, R₄ and R₅ each independentlyrepresent a substituent selected from an alkyl group, an alkoxy group,an alkylthio group, an aryl group, an aryloxy group, an arylthio group,an arylalkyl group, an arylalkoxy group, an arylalkylthio group, anarylalkenyl group, an arylalkynyl group, an amino group, a substitutedamino group and a monovalent heterocyclic group, a unit DA and a unit DBeach independently represent an aromatic ring, a metal complexstructure, a structure represented by the above formula (5), or astructure in which two or more structures selected from an aromaticring, a metal complex structure and a structure represented by the aboveformula (5), which may be the same or different, are bonded; and L is adirect bond or a linking group selected from the following (L-2):

wherein R₁′ represents a hydrogen atom, an alkyl group, an alkoxy group,an aryl group or an aryloxy group, and when a plurality of R₁'s arepresent, R₁'s may be the same or different.
 2. The link compositionaccording to claim 1, wherein the dendrimer compound has a number ofgenerations of 1 to
 5. 3. The link composition according to claim 1,wherein the dendrimer compound comprises a chemical structure in whichat least one dendritic structure selected from dendritic structuresrepresented by the formula (3) and the formula (4) is regularlyrepeated.
 4. The link composition according to claim 1, wherein the corerepresented by the formula (1-2) is represented by the following formula(6-1):

wherein the ring A, the ring B and X are as defined above.
 5. The linkcomposition according to claim 1, wherein the dendritic structurerepresented by the formula (3) is represented by the formula (7-1),(7-2) or (7-3):

wherein the ring A, the ring B and X are as defined above; Ar₁represents a divalent aromatic ring or a divalent metal complexstructure; Ar₂ represents a trivalent aromatic ring or a trivalent metalcomplex structure; and aa and bb each independently represent 0 or
 1. 6.The link composition according to claim 1, wherein the dendriticstructure represented by the formula (4) is represented by the formula(8-1), (8-2), (8-3), or (8-4):

wherein the ring A, the ring B and X are as defined above; Ar₃, Ar₄, Ar₅and Ar₆ each independently represent a trivalent aromatic ring or atrivalent metal complex structure; and Ar₇ represents a tetravalentaromatic ring or a tetravalent metal complex structure.
 7. The linkcomposition according to claim 1, wherein the ring A and the ring B arean aromatic hydrocarbon ring.
 8. The link composition according to claim1, wherein the dendritic structure contains a metal complex structure.9. The link composition according to claim 1, wherein the dendrimercompound further comprises a surface group in addition to the core andthe dendritic structure.
 10. A polymer compound characterised bycomprising a dendrimer compound bonded to an atom constituting the mainchain structure or a side chain of the polymer compound, wherein thedendrimer compound is characterized by comprising a core represented bythe following formula (1-2) and at least one dendritic structureselected from dendritic structures represented by the following formula(3) or (4):

wherein unit CD represents a structure represented by the followingformula (5):

wherein a ring A and a ring B each independently represent an aromaticring, X represents —O—, —S—, —S(═O)—, —SO₂—, —B(R₁)—, —Si(R₂)(R₃)—,—P(R₄)— or —PR₅(═O)—, and R₁, R₂, R₃, R₄ and R₅ each independentlyrepresent a substituent selected from an alkyl group, an alkoxy group,an alkylthio group, an aryl group, an aryloxy group, an arylthio group,an arylalkyl group, an arylalkoxy group, an arylalkylthio group, anarylalkenyl group, an arylalkynyl group, an amino group, a substitutedamino group and a monovalent heterocyclic group, a unit DA and a unit DBeach independently represent an aromatic ring, a metal complexstructure, a structure represented by the above formula (5), or astructure in which two or more structures selected from an aromaticring, a metal complex structure and a structure represented by the aboveformula (5), which may be the same or different, are bonded; and L is adirect bond or a linking group selected from the following (L-2):

wherein R₁′ represents a hydrogen atom, an alkyl group, an alkoxy group,an aryl group or an aryloxy group, and when a plurality of R₁'s arepresent, R₁'s may be the same or different.
 11. An organic luminescentdevice characterized by comprising a layer containing a dendrimercompound between electrodes of an anode and a cathode, wherein thedendrimer compound is characterized by comprising a core represented bythe following formula (1-2) and at least one dendritic structureselected from dendritic structures represented by the following formula(3) or (4):

wherein unit CD represents a structure represented by the followingformula (5):

wherein a ring A and a ring B each independently represent an aromaticring, X represents —O—, —S—, —S(═O)—, —SO₂—, —B(R₁)—, —Si(R₂)(R₃)—,—P(R₄)— or —PR₅(═O)—, and R₁, R₂, R₃, R₄ and R₅ each independentlyrepresent a substituent selected from an alkyl group, an alkoxy group,an alkylthio group, an aryl group, an aryloxy group, an arylthio group,an arylalkyl group, an arylalkoxy group, an arylalkylthio group, anarylalkenyl group, an arylalkynyl group, an amino group, a substitutedamino group and a monovalent heterocyclic group, a unit DA and a unit DBeach independently represent an aromatic ring, a metal complexstructure, a structure represented by the above formula (5), or astructure in which two or more structures selected from an aromaticring, a metal complex structure and a structure represented by the aboveformula (5), which may be the same or different, are bonded; and L is adirect bond or a linking group selected from the following (L-2):

wherein R₁′ represents a hydrogen atom, an alkyl group, an alkoxy group,an aryl group or an aryloxy group, and when a plurality of R₁'s arepresent, R₁'s may be the same or different.